* timer logic is confused by units which are skipped due to failing condition
http://lists.freedesktop.org/archives/systemd-devel/2013-February/008816.html
+* timer logic is also confused if a service it triggers hasn't finished when the next timer elapses:
+ http://lists.freedesktop.org/archives/systemd-devel/2013-February/009021.html
+
Features:
* neither pkexec nor sudo initialize environ[] from the PAM environment?